Process for printing dyestuffs of the dipyrazolanthronyl series



- their use because of their poor printingproper-' thronyl series.

Patented Dec. 23, 1941 PROCESS I OE PRINTING DYESTUFFS THE D IPYRAZOLANTHBONYL SERIES Charles F. Miller, Wilmington, DeL, assignor to E. I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware no Drawing. Application November 24, 1939, Serial No.305,924 9 Claims. (01 9-70) This invention relatesto an improved process for printing vat dyestuffs of the dipyraz'olan- The N,N'-dialkylandthe N-alkyl-l Y-aralkyl dipyrazolanthronyls which have been recognized as valuable vat dyeing colors are limited in ties, forv it has been recognized that these dipyrazolanthronyl dyes give prints that are .de-

' flcient in fullness, brightness and depth of shade The following examples are given to illustrate the invention. Theparts used are by weight.

With the use of the triethanolamlne in conjunction with the metallic catalyst the dipyrazolanthronyl dyes are printed with the conventional printing pastes made up with the usual thickeners. a

when applied by the conventional printing methods, and are therefore of no real value as printing colors.

while attempts have been made to improve the printing properties of these colors by introducing various substituer'its into the molecule the introduced substituent usually varies the shade of the dyestuif, in some cases alters its dyeing and fastness properties and invariably it adds materially to the cost of the desireddyestufi.

It is therefore an object of this invention to provide a process whereby the dyes of the dipyrazolanthronyl series can be printed in full bright shades by the conventional alkali carbonate, alkali sulfoxylate-formaldehyde method. It is a further object of the invention to provide vat color assistant pastes of dyes of the dipyrazolanthronyl series which can be added to the conventional printing pastes to. give full bright prints when printed and developed by the usual vat dye printing methods.

I have found that the commercial dyes of the dipyrazolanthronyl series which have heretofore been of no value as printingcolors canbe printed in full bright shadeswith the usual carbonate, sulfoxylate-iormaldehyde. printing pastes when there is added to the dyestufl printing paste A conventional starch-British gum-thickening paste'may be prepared as follows:

100 parts of wheat starch and 250 parts of British gum, are pasted in 050 parts of water I 1000 parts I This paste is heated to the boil-for 10 minutes and cooled to 170 F. d

A conventional printing gum may be prepared as follows: 1

To 650 parts of the starch-British gum-thickener at 170 F., there are added 150 parts of potassium carbonate and 50 parts of glycerin. The paste is then cooled to 140 F., and 150 parts of sodium sulfoxylate-formaldej hyde are added, giving 1000 parts of-printing gum.

Example 1 5 parts'of a dyestufl paste of-N-N'-diethyldipyrazolanthronyl containing 22% color solids, 10 parts of triethanolamine, 0.2 of apart of ferrous chloride and 84.8 parts of the printing gum,

'paste. Cotton and rayon piece-goods I may be printed with the above printing paste in the preparation. triethanolamme and a small amount 40 color ager of the Mather Platt type, oxidized for or a salt, oxide or hydroxide or a metal or the class co sting of copper.. a a

The assistants may be added to the printing composition or they may be incorporatedwith the vat color to form an assistant color paste which may be added to the conventionl printing paste preparations.

I have'found that. amine that may be used can be varied within wide limits. From 4 to 10 parts of the triethariolaminje with from 0.1 to 0.2 part. of the "imetaliicwsalt, oxide orhydroxide per part of color employed (100% color basis) give full bright prints of ferrous iron, zinc, tin and the amount of methanolas above prepared, are milled into a smooth usual manner, dried, aged 5 minutes in a vat are thus printed in a deep bluish-red design.

In place of the N -N'-diethyldipyrazolanthronyl the N methyl-N'-isopropyl-2:2'-dipyrazolanthr o 1 may be used if a yellower shade is desired, an that obtained in Example 1.

the dipyrazolanthronyl colors. as.

Example 2 The following example illustrates theuse of a vat dye assistant dye paste containing the triethanolamine and metallic salts already incor- 2 I U ported therein. The assistant dye paste may preparedior use as follows:

100 parts of the vat dye paste of N-N'-diethyldipyrazolanthronyl containing 22% color solids 50 parts of triethanolamine and 1 part of ferrous chloride, are evaporated to drive of! 51 parts of water, leaving 100 parts of vat color assistant paste which is milled to insure thorough mixing of the ingredients.

dyestuil' oi the group consisting of N,N'-dialkyldipyrazolanthronyls and N-alkyl-N'-aralkyl-dipyrazolanthronyls, triethanolamine and a metallic compound of the group consisting of salts, oxides and hydroxides of a metal of the roup consisting of ferrous iron, tin', zinc and copper.

2. A vat dyestuif printing paste comprising a N,N-dialkyldipyrazolanthronyl, triethanolamine and ferrous chloride.

3. A vat dyestufi preparation for use in textile printing comprising an N,N'-dialkyldipyrazolanthronyl,.triethanolamine and a metallic comsoaped, rinsed and dyed as in Example 1, a. full as bright bluish-red design is obtained on a blue background.

It is tobeunderstood that other thickeningpastes andfprinting gum preparations may be employed with these colors when the triethanolamine and metallic catalyst are employed. The above examples are given. merely to illustrate, and notas a limitation upon; the invention.

The triethanolamine and metallic salts when used together as above described have been found to very materially improve the printing prop- .erties of the alkylated dipyrazolanthronyls which are illustrated by those given inthe above ex-' amples and which include the symmetrical dipyrazolanthronyls in which the two alkyl groups are identical and the unsymmetrical in which the alkyl groups on the two nitrogen atoms are dissimilar, including those particularly, described in copending application of Perkin and Carr, Serial No. 139,100, .flled April 28, 1937. The following colors further illustrate the dyes or this class which exhibit good printing properties when i printed bythis process; N-ethyl-N'-benzyldipy-' razolanthronyl, dimethyldipyrazolanthronyl or 7 mixtures of these colors such as a mixture of f N methyl N a isopropyldipyrazolanthronyl and N,N'.-diethyldipyrazolanthronyl, etc.

I claim:

l. A vat d'yestufl printing paste comprising a 1 pound of the group consisting of salts, oxides and hydroxides of a metal. of the group consisting of ferrous iron, tin, zinc'and copper.-

4. A vat dyestufi preparation for use in textile printing comprising an N,N'-dialkyldipyrazolanthronyl, triethanolamine and ferrous chloride.

5. A vat dyestufi preparation for use in textileprinting comprising N,N' -diethyldipyrazolan- 7. A vat dyestufi "preparation for use in textile printing comprising N-methyl-N'-isopropyldipyrazolanthronyl, triethanolamine and a metallic compound of the group consisting of salts, oxides and hydroxides of a metal of the group consisting of ferrous iron, tin, zinc and copper.

8..A vat dyestufl preparation for use in textile printing comprising .N,N'-dimethyldipyrazolanthronyl, triethanolamine and a metallic compound of the group consisting of salts, oxides and hydroxides of a metal of the group consisting of ferrous iron, tin, zinc and copper.

9. The process of printing textile materials with a vat dyestufl of the group consisting oi N,N'-dialkyldipyrazolanthronyls and N-alkyl-N'- aralkyldipyrazolanthronyls which comprises applying said djpyrarolanthronyl dyestufl to said material in a printing preparation containing triethanolamine' and a compoundof the class consisting ofssalts, oxides and hydroxides oia metal of, the-class consmting of iron, tin, zinc and copper. i v CHARLES E. MILLER. 

